IWS Pro FlexiTank with Pipes & Pump — Complete Flood & Drain Reservoir Kit
Best for: IWS Pro system users upgrading to automatic watering without the faff of manual top-ups
Our thoughts
If you're already running an IWS Pro flood and drain setup, this takes the guesswork out of maintaining water levels. It's a complete kit — tank, pump, pipes, the lot — and it assembles in minutes. One less thing to babysit, which is exactly what you want when you're trying to keep things stable.
The IWS Pro FlexiTank with Pipes & Pump is a complete, ready-to-connect reservoir system designed to integrate seamlessly with your IWS Pro 25mm flood and drain setup. It's a flexible fabric tank that folds flat for storage, supplied with a high-flow pump (3000–4000 litres per hour), irrigation pipework, and all the fittings you need to get it working. In simple terms: automatic water top-ups that actually fit your system, without buying bits piecemeal and hoping they work together.
How it compares
Against other flood and drain reservoir options, this is system-specific and fully integrated.
- Complete kit approach — pump and pipes included, not sold separately
- Faster assembly than rigid plastic tanks (folds flat, sets up in minutes)
- High-flow pump capacity built in, saving a separate purchase
- IWS Pro compatibility is guaranteed; no guessing about fittings
- More compact storage than rigid water butts or tanks
If you're already committed to IWS Pro, this is the natural choice. If you're running AutoPot or a different system, look elsewhere — this is built for IWS only.
Usage guidance
Assembly
Unroll the tank, slide the five support legs into the vertical slots in the fabric, and fit the irrigation fittings into the holes at the top. Connect the piping using the elbow connections and markings on the outside. The whole process takes minutes, not hours.
Connection to your IWS Pro
Two drain pipes connect to the MJ-1000 pumps inside your IWS Pro Brain Bucket. One fill pipe connects to the pump inside the FlexiTank. The kit includes everything you need — no adapters to chase down.
Operation
Once connected, the pump automatically tops up your system, keeping water levels stable and reducing manual feeding. This maintains consistent nutrient delivery and helps prevent root-borne issues by keeping oxygen levels steady.
Capacity choice
Available in 250L, 400L, 750L, and 1000L. Larger tanks mean fewer manual top-ups and more forgiving EC/pH drift. Pick based on your grow room size and how often you want to refill.
Technical specifications
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Tank construction: Thick, flexible fabric with zippered lid and five support legs
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Available capacities: 250L, 400L, 750L, 1000L
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Pump supplied: NJ-3000 water pump (3000 litres per hour) — alternative high-pressure 4000lph pump available depending on stock
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Pipe configuration: Two drain pipes (to IWS Pro Brain Bucket), one fill pipe (to tank pump)
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Fittings: All required irrigation connectors and elbow joints included
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Storage: Packs flat for easy transport and storage between crops
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Assembly time: Approximately 10–15 minutes
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Compatibility: IWS Pro 25mm flood and drain systems only
Who this is for
- Existing IWS Pro system users ready to move beyond manual top-ups
- Growers running multiple flood and drain trays who need automated water management
- Anyone prioritising quick setup and system-specific reliability over universal compatibility
- Growers who want their nutrient solution kept stable without constant adjustment
- Flood and drain operators who've had issues with water level drift mid-cycle
This is not for AutoPot users, NFT systems, or standalone DWC operations. It's IWS Pro territory only.
Our take
This is a no-nonsense upgrade for IWS Pro growers. You get the tank, the pump, and the pipes all matched to work together — no compatibility guessing, no missing adapters halfway through assembly. It does what it's supposed to do: keep your water topped up automatically so you can focus on the actual growing.
If you're already running IWS Pro and still manually feeding your reservoir, this is worth picking up. It cuts out a job, adds stability, and the complete kit approach means you're not assembling a Frankenstein's monster from three different suppliers. Good time to buy while clearance stock lasts.
